Flyers that warn about penalties for supporting illegal immigration have been posted in Washington, D.C., and the city's mayor is telling people to remove them.

Official-looking flyers with the U.S. Department of Homeland Security logo and the words U.S. Immigration and Customs Enforcement say "SANCTUARY CITY NEIGHBORHOOD PUBLIC NOTICE" and warn of jail time for harboring "illegal aliens." The flyers are glued to light poles and utility boxes.

"Just like false reports of immigration checkpoints or random sweeps, notices like these are dangerous and irresponsible," the spokeswoman continued. "Any person who actively incites panic or fear of law enforcement is doing a disservice to the community, endangering public safety and the very people they claim to support and represent.”

D.C. Mayor Muriel Bowser instructed residents to tear down the flyers. "DC is a sanctuary city. Clearly the flyer is meant to scare and divide our residents. We won't stand for it. #DCValues," she wrote.

"If this was fake, it's obviously the people trying to spread hate around the neighborhood, and that's not OK," said Alexa Disch, who works in Southwest.

D.C. is a proud sanctuary city that issues provisional driver's licenses to undocumented residents. Police do not ask about residency status, and in January Bowser announced the creation of a legal defense fund to help immigrants.

“The fake fliers were clearly designed to convey the impression of authenticity, and I believe they were posted in order to target and intimidate immigrants and their families living in the District," Norton wrote. "D.C. is a city that welcomes and provides sanctuary to people from all over the world, and we believe a federal investigation to determine who is responsible is fully warranted.”

The Takoma Park, Maryland, Police Department sent out a community advisory informing residents of the flyers and asking them to report them and take them down if they see them.